SYNTHESIS F ASPIRIN SYNTHESIS PURIFICATIN CHARACTERIZATIN
ASPIRIN: SME BACKGRUND PATENTED BY BAYER IN 1893 NE F THE LDEST DRUGS NE F THE MST CNSUMED DRUGS (PRDUCTIN IN THE US IS 10 MILLIN KG/YEAR)
ASPIRIN: BILGICAL ACTIVITY ANALGESIC (PAINKILLER) ANTIPYRETIC (FEVER REDUCER) ANTI-INFLAMMATRY (INHIBITIN F THE SYNTHESIS F PRSTAGLANDINS) SIDE EFFECTS: GASTRIC IRRITATIN, BLEEDING APPARITIN F NEW ANALGESICS (TYLENL)
ASPIRIN: THE MLECULE H acetyl salicylic acid (aspirin)
RGANIC BACKGRUND ALCHLS ALCHLS R H ALIPHATIC ALCHLS: HYDRXYL DERIVATIVES F SATURATED HYDRCARBNS H 3 C H methanol ethanol ENLS: HYDRXYL DERIVATIVES F UNSATURATED HYDRCARBNS R H H H R enol phenol
RGANIC BACKGRUND CARBXYLIC ACIDS R H H H H. C H H formic acid acetic acid benzoic acid
RGANIC BACKGRUND ESTERIFICATIN R 1 H + H + H R 2 R 1 R 2 carboxylic acid alcool ester This is an equilibrium!
RGANIC BACKGRUND ESTERIFICATIN MECHANISM H + H H 2 + R 1 H H R 2 R 1 H R 1 H carboxylic acid alcool R 2 + H R 2 -H + R 1 ester R 2
RGANIC BACKGRUND ACIDITY: A REVIEW BRNSTED-LWRY ACID SUBSTANCE THAT CAN DNATE A PRTN LEWIS ACID SUBSTANCE THAT ACCEPTS LNE-PAIR ELECTRNS AH + H 2 A - + H 3 + K A = [H 3 + ][A - ] / [AH] PK A = -LG K A Acid pk a water 14.0 Acetic acid 4.75 Benzoic acid 4.19 Formic acid 3.75 Sulfuric acid 1
REACTIN H H H 2 S 4 + heat + H H acetic anhydride salicylic acid acetyl salicylic acid (aspirin) acetic acid
REACTIN MECHANISM H H + H + H H H -H + H + H
SYNTHESIS PRCEDURE MIX SALICYLIC ACID (SLID) WITH ACETIC ANHYDRIDE (LIQUID) AND A CATALYTIC AMUNT F H 2 S 4. HEAT FR 10 MIN AT 90 0 C. CL DWN T RM TEMPERATURE AND ADD WATER (CRYSTALLIZATIN SLVENT). INDUCE CRYSTALLIZATIN. FILTER THE CRYSTALS.
PURIFICATIN BY RECRYSTALLIZATIN WHAT IS RECRYSTALLIZATIN? METHD RAPID AND CNVENIENT WAY F PURIFYING A SLID RGANIC CMPUND THE MATERIAL T BE PURIFIED IS DISSLVED IN THE HT APPRPRIATE SLVENT AS THE SLVENT CLS, THE SLUTIN BECME SATURATED WITH RESPECT T THE SUBSTANCE, WHICH THEN CRYSTALLIZE IMPURITIES STAY IN SLUTIN CHSE THE SLVENT DISSLVE THE SLUTE (FILTER SUSPENDED SLIDS) CRYSTALLIZE THE SLUTE CLLECT AND WASH THE CRYSTALS DRY THE CRYSTALS
ASSESSMENT F PURITY: LKING FR PRPERTIES PHYSICAL PRPERTIES CHEMICAL PRPERTIES PHYSICAL APPEARANCE SLUBILITY MELTING PINT INFRARED SPECTRA PERCENT YIELD PTENTIMETRIC TITRATIN PHENL TEST
ASSESSMENT F PURITY: PHYSICAL APPEARANCE PHYSICAL STATE (SLID? LIQUID?..) CLR DR TEXTURE HMGENEITY IN CMPSITIN
ASSESSMENT F PURITY: SLUBILITY (NN MANDATRY) IN A TEST TUBE, TRANSFER A SMALL AMUNT F YUR PRDUCT (END F A SPATULA) ADD ~1/2ML F SLVENT DETERMINE SLUBILITY AT RM TEMPERATURE IF NT, GENTLY HEAT AND DETERMINE SLUBILITY AT HIGHER TEMPERATURE TEST SEVERAL RGANIC SLVENTS AND CMPARE WITH LITTERATURE
ASSESSMENT F PURITY: MELTING PINT MELTING PINT CHARACTERIZE THE CMPUND RANGE F THE MELTING PINT INDICATE THE PURITY F THE CMPUND METHD: SCANNING F THE TEMPERATURE UNTIL MELTING CCURS. DETERMINE START AND END TEMPERATURE F MELTING. DN T HEAT T FAST!! (<1 0 C / MIN)
ASSESSMENT F PURITY: INFRARED SPECTRA DISSLVE THE PRDUCT IN CHLRFRM AND BTAIN THE IR SPECTRUM. YU CAN ALS PREPARE A PELLET IN KBR. ASSIGN THE PEAKS D YU SEE IMPURITIES? CMPARE WITH THE REFERENCE SPECTRUM.
ASSESSMENT F PURITY: PERCENT YIELD DEFINITIN: %YIELD = N EXP /N TH WRITE DWN THE REACTIN WITH THE CRRECT STECHIMETRY. EX: A+B C PREPARE A CHART LIKE BELW AND CALCULATE YIELD. m A (g) or V A (ml) n A (mol) m B (g) or V B (ml) n B (mol) m C (g) theoretical n C (mol) theoretical m c (g) experimental n C (mol) experimental
ASSESSMENT F PURITY: PHENL TEST AND VISIBLE SPECTRSCPY PHENL REACT WITH FECL 3 (AQ) T GIVE A DEEP PURPLE CMPLEX. PHENL IS NT PRESENT IN THE PRDUCT BUT IN NE F THE REACTANT. THIS TEST INDICATE THE PRESENCE F UNREACTED STARTING MATERIAL (QUANTITATIVE ANALYSIS PSSIBLE VIA VISIBLE SPECTRSCPY).
H H + Fe 3+ Deep purple complex salicylic acid
ACETYLSALICYLIC ACID (MRE CMMNLY KNWN AS ASPIRIN) BY VIKTR PLITES
CHEMICAL STRUCTURE FRMULA: C 9 H 8 4 SYSTEMATIC NAME: 2-ACETXYBENZIC ACID HAS A BENZENE RING BACKBNE CARBXYLIC ACID ESTER GRUP N THE 2ND CARBN IN BENZENE RING.
PHYSICAL PRPERTIES Density: 1.40 g/cm 3 Melting Point: 135 C Boiling Point: 140 C Solubility in Water: 3 mg/ml at 20 C
CHEMICAL PRPERTIES ACETYLSALICYLIC ACID SLWLY DECMPSES BY HYDRLYSIS INT ACETIC AND SALICYLIC ACIDS IN THE AQUEUS MEDIUM. HYDRLYSIS F ACETYLSALICYLIC ACID IS ACCELERATED IN SLUTINS F AMMNIUM ACETATE, R ACETATATES, CARBNATES, CITRATES, R HYDRXIDES F THE ALKALI METALS. ACETYLSALICYLIC ACID IS A WEAK ACID WITH AN ACID DISSCIATIN CNSTANT, KA, F 3.2 X 10^-4.